1. Field of the Invention
The present invention relates to a fluid conveying device, and more particularly, to a multi-channel fluid conveying apparatus employed as a micropump structure.
2. Description of Related Art
Currently in various fields, whether in medicine, computer technology, printer, or energy, product development toward compact-sized or micro-sized becomes a trend. As far as micropumps, sprayers, ink-jet printheads, or industrial printing devices are concerned, a fluid conveying structure involved therein is considered a key technique. Therefore, how to breakthrough technological bottlenecks by a creative structure turns out to be a significant issue of developments.
Referring to FIG. 1, an exploded view illustrating a conventional micropump structure, the micropump structure 10 comprises a valve seat 11, a valve cover 12, a valve membrane 13, a micro-actuator 14, and a pump cover 15. The valve membrane 13 includes an inlet valve structure 131 and an outlet valve structure 132. The valve seat 11 includes an inlet channel 111 and an outlet channel 112. A pressure chamber 123 is defined by and between the valve cover 12 and the micro-actuator 14. The valve membrane 13 is interposed between the valve seat 11 and the valve cover 12.
Upon a voltage acting on two poles located at top and bottom of the micro-actuator 14, an electric field will be effected to bend the micro-actuator 14. When the micro-actuator 14 deforms and bends upward to a direction X, an increased volume will occur in the pressure chamber 123, so that a suction force is produced and the inlet valve structure 131 of the valve membrane 13 opened. This will make a fluid be sucked from the inlet channel 111 of the valve seat 11, and flow through the inlet valve structure 131 of the valve membrane 13 and an inlet valve channel 121 of the valve cover 12, and into the pressure membrane 13. If, however, to the contrary, when the micro-actuator 14 bends toward a direction opposite to the direction X due to a change of the electric field, the volume in the pressure chamber 123 will be compressed, such that a thrust will occur against the fluid inside the pressure chamber 123. This will make the inlet valve structure 131 and the outlet valve structure 132 of the pressure membrane 13 subject to downward thrust, such that the outlet valve structure 132 is opened and that the fluid flows from the pressure chamber 123, and through an outlet valve channel 122 of the valve cover 12, the outlet valve structure 132 of the pressure membrane 13, and the outlet channel 112 of the valve seat 11, and out of the micropump structure 10. This will complete a fluid conveying process.
In spite of the fact that the conventional micropump structure can still achieve the purpose of fluid conveyance, it adopts such a design that the mono-pressure chamber is incorporated with the mono-flow conduit, the mono-inlet and outlet, and the mono-paired valve structure. In case the conventional micropump structure 10 is employed to mix two different fluids at different proportions, two extra pumps are necessary, with first picking up different proportions of the fluids and then agitating and mixing the same. Thereafter, the mixed fluids are delivered to the micro-pump structure 10 for the conveyance of the fluids, as mentioned above. Or alternatively, if only one single pump is used. This, however, needs to incorporate an externally-attached flow adjusting valve, and as a result, makes the whole pumping system more complicated.
It is understood, therefore, that to develop a multi-channel fluid conveying apparatus so as to improve the defects inherent in the conventional art becomes an urge.